192 RESULTS WITH SULPHATE OF AMMONIA, 



Here the crop was nearly tripled ; an effect dependent, no 

 doubt, in some measure on the state of the land. 



These experiments prove the value of ammoniacal liquor, and 

 afford a strong presumption in favour of carbonate of ammonia 

 applied alone ; but, as I have already said, they do not satisfac- 

 torily bring out the special and unaided action of carbonate of 

 ammonia. 



Pure carbonate of ammonia is too high in price to be recom- 

 mended for field experiments, but trials on a small scale may be 

 made with it, especially in comparison with the other salts of 

 ammonia, which are more usually employed as manures. 



4. Results of experiments with sulphate of ammonia. 



The sulphate has been more extensively employed as a 

 manure, and more generally with a profit, than any other of the 

 salts of ammonia. This has arisen chiefly from its greater 

 abundance, and from the comparative lowness of its price. It 

 is to corn and grass crops that it has hitherto been most fre- 

 quently applied. 



1. On wheat. In 1847, Mr Main applied it on the 1st of 

 February to a portion of Taunton-Dean wheat, with the follow- 

 ing result in comparison with sulphate of soda : 



* 



Grain. Straw. 



No application gave . . 27^ bush. 19^ cwt. 

 Sulphate of ammonia, 2 cwt. 33 j ... 29g ... 



Sulphate of soda, 2 cwt. . 32 ... 24| .. 



I have added the result of the action of sulphate of soda, for 

 the purpose of marking the difference in the effects of the two 

 sulphates. Both largely increased the produce of grain, and 

 nearly to the same extent, but the sulphate of ammonia added 

 about five hundredweight more to the produce of straw. It had 

 the usual effect of the salts of ammonia in promoting growth 

 more than mineral sulphates are observed to do. 



2. On oats. The following table exhibits the results of four 

 experiments made upon oats, top-dressed in the spring of 1843, 

 on different farms near Turriff, in Aberdeenshire : 



